I believe it's something with TC 2017, i do remember this rotating every place there was an mitered roofslab.
The ide'a is that the pdf take in the fault, and not what is TC's workaround for that problem, before they got it fixed.
I get bored of it and start to just add an 1 mm solid on top of the roofslab and attach materials to that. (WP by 3 point), but if possible i did make them as roof first and give material before i used convert to roofslab on the roof's, most of the times it then come out correct
Attached is from v 2018 as for some reason i dont have LW or RedSDK in v 2017 anymore, and i dont care to reinstall or whatever to fix it
Rooftiles is with Autoplane scale set to 1 and pic. is scaled up and you can see 5 roof slabs in the Picture
V18, V19, V20, V21, 2015/ 16/ 17/ 18 Pro. Platinum
Deluxe V20, V21, 2015/ 16/ 17
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